Adsorbent filters have a variety of uses, including uses in electronic equipment and chemical manufacturing and storage. For example, in the computer industry, adsorbent filters are used within the housings or casings of electronic devices to protect the electronic components from contaminants and impurities, such as water vapor, acid gases, and volatile organic compounds. For example, disk drives often include adsorbent filters within the enclosure of the disk drive and/or over an opening in the disk drive housing to protect the drive components and the disks from contaminants. Without such protection, these contaminants can lead to stiction, corrosion, and, in some instances, drive failure. Inclusion of an adsorbent filter improves the performance of the disk drive and extends its life. Typically, the adsorbent filter includes an adsorbent material, such as activated carbon or a desiccant, within the filter material. Pores within the filter allow contaminants to diffuse through the filter material and be adsorbed by the adsorbent material.
U.S. Pat. No. 5,593,482 discloses a thin compact adsorbent assembly for adhesively mounting in an enclosure such as a computer disk drive. This self-stick adsorbent assembly has a low profile container for selectively adsorbing gaseous components. The assembly comprises one or more layers of adhesive, one of which adheres the assembly to a surface of the disk drive. The assembly also includes one or more layers of adsorbent or reactant material and a layer of filter material.
As aerial densities continue to grow and flying heights between the disk and read head lessen, disk drives are becoming increasingly sensitive to contamination. Adhesively mounting a filter assembly on a surface of a disk drive enclosure may contribute to this contamination. For example, if the adhesively mounted filter assembly is removed or repositioned, the adhesive may leave an adhesive residue on the surface of the disk drive enclosure. If the adhesive is left exposed, the adhesive residue may outgas (or offgas). Outgassing includes the release and/or production of gaseous or other contaminants by the adhesive. Outgassing by the adhesive residue can produce additional contaminants that are introduced into the disk drive environment. Further, the residue may accumulate and retain particulate contaminants and dust. These contaminants, or the adhesive itself, could loosen, flake, or become dislodged, providing debris in the disk drive enclosure. This debris can permanently damage a disk drive. To eliminate or reduce the contaminants caused by the adhesive residue, the adhesive residue may be removed and the surface cleaned. A solvent may be needed to thoroughly clean the surface of adhesive; however, these solvents may also cause contamination that can damage the drive assembly. Gaseous contaminants, similar to those produced by the adhesive residue outgassing, are also produced by solvents used to remove the residue.
In addition to eliminating or reducing contaminants caused by adhesive, eliminating the adhesive residue on the disk drive enclosure also greatly reduces the number of disk drive assemblies that might be thrown away. Disk drive assemblies are often discarded if the filter is mounted incorrectly because it is easier, less expensive, and/or results in less contamination to get a new assembly than to clean the contaminated one.